Roof structure repairs in Lancashire

Area: Lancashire
Pricing region: North West
Ground: Clay in parts
Towns listed: 20

What should you know about the ground under Lancashire?

Parts of Lancashire lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. What you mostly find across Lancashire: stone and brick mill terraces, seaside villas in Blackpool and Lytham, and inter-war and post-war semis.

How we usually approach roof structure repairs

Tying in roof spread

New ties, collars or steel straps connect opposite rafters, or fix the rafter feet and wall plate firmly to the ceiling joists, so the outward thrust is resisted. Leaning wall heads are strapped back to the roof, and a badly spread roof may need partly rebuilding first.

Best for: Walls pushed out at eaves level by spreading rafters

Repairing or doubling rafters

Cracked, sagging or rotten rafters are strengthened by fixing a new timber alongside, often called doubling, and rotten rafter feet are cut back and spliced. The work is usually done from inside the loft with the tiles left in place, unless the covering is coming off anyway.

Best for: Individual rafters that have cracked, sagged or rotted at the feet

Purlin and strut strengthening

Undersized purlins are strengthened with extra timber or replaced, and new struts are taken down to a load-bearing wall. Where there is no suitable wall, an engineer designs the load path. Temporary props hold the roof while members are changed.

Best for: Sagging slopes, slim purlins and struts removed from the loft

What happens during roof structure repairs, step by step?

Engineer’s design where needed
Where purlins, struts or ties must be redesigned, or the roof carries a heavier covering, an independent chartered structural engineer is appointed to specify the work. We can arrange this, and their design sets the sizes and fixings.
Written quote
You receive a no-obligation written quote listing each timber repair, any ties or straps, propping, scaffolding and making good. Once the repair is specified, the figure becomes a fixed price in writing.
Prop, strengthen and tie
The roof is propped where members are being changed, then rafters, purlins, struts and ties are repaired or added as specified. Coverings disturbed by the work are relaid, and building control inspects where the work needs it.

What to look for before calling about roof structure repairs

Top of an outside wall leaning out at eaves level
Ridge line dipping in the middle when seen from the street
Struts, collars or ties cut out or missing in the loft
Horizontal cracks in the wall just below the eaves or ceiling line

Roof structure repairs prices in Lancashire

Prices in Lancashire are worked out on North West rates. They include VAT and are a starting point: access, the extent of the damage and whether an engineer or building control is involved all move the figure.

Guide prices inc VAT on North West rates. Items marked est. are our estimates.
Item	Guide price	Per
Repairing or doubling a rafter	£290 – £575	per rafter
Purlin and strut strengthening	£1,150 – £2,900	per roof
Tying in roof spread (straps and ties)est.	£770 – £2,400	per roof

Roof structure repairs: purlin and struts added, roof spread tied in. Indicative drawing, not to scale.

Do you need approval for roof structure repairs in England?

In England, underpinning and other work that alters or strengthens a wall or foundation is building work under the Building Regulations (Part A, structure), so building control approves and inspects it. Like-for-like repairs often are not, and we tell you which applies before a price is agreed. Work to a party wall, or excavation close to a neighbour’s foundations, can also need a notice under the Party Wall etc. Act 1996.

Roof structure repairs near you in Lancashire

Questions about roof structure repairs in Lancashire

Does the ground around Preston cause cracking?

Lancashire is mostly glacial till over sandstone and mudstone, with the Burnley and Accrington coalfield in the east and soft coastal and estuarine ground on the Fylde. Old mill and mine sites leave made ground in many towns. Parts of Lancashire lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Only an investigation on site can say why a particular building has moved.

How much will roof structure repairs cost in Lancashire?

On North West rates, roof structure repairs starts from about £290 per rafter, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.

Can the roof be strengthened without removing the tiles?

In most cases, yes. Doubling rafters, adding struts and fitting ties can all be done from inside the loft with the coverings in place. Tiles usually only come off where timber near the eaves is badly decayed, or the roof is being re-covered anyway.

Do I need a structural engineer for roof repairs?

For like-for-like repairs to a few rafters, often not. Where purlins, struts or ties are being redesigned, the covering is getting heavier or the walls are being pushed out, you usually do. Where the repair needs an engineer’s design or sign-off, an independent chartered structural engineer is appointed, and we can arrange this.

What is roof spread?

Roof spread is when the feet of the rafters move outward because nothing is tying them together firmly enough. As they spread, the ridge drops and the tops of the walls are pushed out, often with a horizontal crack below the eaves. It is fixed by adding ties, collars or straps, sometimes with rebuilding.